Figure 4-3 Passenger Transportation Services Index: January 2000–December 2015
1 The passenger Transportation Services Index (TSI) includes local transit, intercity passenger rail, and passenger air transportation,
that have been weighted to yield a monthly measure of transportation services output.
2The combined TSI includes available data on freight traffic, as well as passenger travel, that have been weighted to yield a monthly
measure of transportation services output.
NOTES: TSI, created by the U.S. Department of Transportation, Bureau of Transportation Statistics, is a measure of the month-to month
changes in the output of services provided by the for-hire transportation industries. TSI data change monthly due to the use of
concurrent seasonal analysis, which results in seasonal analysis factors changing as each month’s data are added.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics, Transportation Services Index, available at www.
bts.gov as of February 2016.